<< Wow.. the language of this message seems to suffer a similar
tri-chotomy.

> Because of the nature of the project's translation technique used> so far, I would like to be able to compile the PDL into a "semantic> database / repository" and generate the final language output from> that. Experience indicates that the language will reflect the internal> structure of the repository and thus an information model may be the> best/first port of call, however the repository may be created to> reflect the language if the language is the right choice. I am willing> to consider either and other possibilities.

Assuming that what you are looking for is some kind of recommendation,
you could probably get the most flexibility by parsing your top-level
into a relational database that includes as much information (derived
and defined) as possible. This allows the backend to generate code
from whatever information it likes, without being constricted by some
of kind of efficient model.
>>

Thanks but I started that way anf then replaced a relational database with an
object network, that is itself generated by it's own data-description ; a
little recursive ... a lot more efficient in both time & effort.